I've been trying it for about two years, I usually have an S19, also with 6 s19 and 750Th/s full months.
During this time those doubts arise, I continue with everyone in Viabtc or I try my luck in ckpool, if I find a block I would get what I would have to be at least 15 years mining in viabtc, of course, if they do not find a block I do not recover the investment.... A complicated dilemma to fear clear
I think there is a thin line between lottery/trying your luck vs gambling, going full blast with nearly 1PH to solo mine to me is addictive gambling. if you have 100PH worth of hashrate then that would be a different story, but if all you got 2PH and you point 50% of it to solo -- it's bad gambling, let alone pointing 100% of your hashrate, but it is just me, I know everyone is different.